A.C Fundamentals, Circuits and Circuit Theory Bank PO MCQ... Quiz Questions

1. Calculate the power by two wattmeter (W1 & W2) method, if one of the wattmeter (W2) reading is taken after reversing.

A W1 * 2 B W1 only C W1 - W2 D W1 + W2

2. What is the line voltage in 3 phase system if the phase voltage is 240V ?

A 380 Volt B 400 Volt C 415 Volt D 440 Volt

3. How the low power factor (P.F) can be improve in AC circuit?

A By connecting resistance in series. B By connecting capacitor in series. C By connecting inductor in series D By connecting capacitor in parallel

4. What relationship is illustrated in between the current and voltage?

A Current and voltage are "in phase" B Current and voltage are in out of phase C Current lags behind the voltage D Current leads ahead of the voltage

5. Which AC circuit contains the phase relation between voltage (V) and current (I)?

A Pure resistive circuit B Resistance and inductance circuit C Resistance and capacitance circuit D Resistance, inductance and capacitance circuit.

6. What is the purpose of phase sequence meter?

A To control the speed of 3 phase motor. B To protect motor against short circuit fault C To indicate the incorrect phase sequence of 3 phase D To ensure the correct phase sequence of 3 phase system

7. In which condition resonance will occur in R-L-C series circuit?

A Inductive reactance (XL) is zero B Inductive reactance (XL) is equal to capacitive reactance (XC). C Inductive reactance (XL) is greater then capacitive reactance (XC). D Inductive reactance (XL) is less than capacitive reactance (XC).

8. In which 3 phase system, the artificial neutral is required to measure the phase voltage?

A 3 wire star connected system B 4 wire star connected system C 3 wire delta connected system D 4 wire delta connected system

9. Calculate the impedance of the circuit,R = 5 Ohm, XL = 36 Ohm, XC = 24 Ohm

A 69 Ohm B 65 Ohm C 13 Ohm D 12 Ohm

10. What is the resistance of the inductive coil takes 5 A current across 240V, 50 Hz supply at 0.8 power factor?

A 48 Ohm B 42.5 Ohm C 38.4 Ohm D 26.6 Ohm